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Calcimator

Student-Teacher Ratio Calculator

Calculate student-teacher ratios and resource impact from class size changes.

Inputs

Results

Current Ratio

18.2:1

Avg Class Size20 students
Effective Staff (FTE)27.5
Additional Teachers Needed1
Meets Target?No
Ratio if +1 Teacher17.5:1
Ratio if -1 Teacher18.9:1
How to Use This Calculator
  1. Enter Total Students — the full enrollment count for the school, grade, or department.
  2. Enter Total Teachers — the number of full-time classroom teachers.
  3. Add Teacher Aides and set their Aide Equivalency (%) — 50% means each aide counts as half a teacher for ratio purposes.
  4. Set Target Ratio — the maximum students-per-teacher your policy or accreditation standard requires.
  5. Review Current Ratio and Meets Target? to determine if staffing is compliant.
  6. Use Additional Teachers Needed and the Ratio if +1 Teacher outputs to make evidence-based hiring decisions.

How the result changes with Total Students

Total StudentsCurrent Ratio
1,00136.4:1
3,501127.3:1
6,500236.4:1
9,000327.3:1

What each input means

Total Students
Total student enrollment in the school or grade level.
Total Teachers
Number of full-time classroom teachers.
Teacher Aides
Number of classroom aides or paraprofessionals.
Aide Equivalency (%)
How much an aide counts toward staffing (50% = half a teacher).
Target Ratio
Desired maximum students per teacher.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Total Students = 500, Total Teachers = 25, Teacher Aides = 5, Aide Equivalency (%) = 50 = 5 input(s) provided
  2. Calculate Current Ratio
    Current Ratio
    18.2 = 18.2
  3. Calculate Avg Class Size
    Avg Class Size
    20 = 20
  4. Calculate Effective Staff
    Effective Staff
    27.5 = 27.5

Engine last updated .

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